<!DOCTYPE html>
<meta charset="utf-8"/>
<title>Padding/border/margin on mfrac (reference)</title>
<style>
  @font-face {
    font-family: FractionFont;
    src: url("/fonts/math/fraction-rulethickness10000.woff");
  }
  mfrac {
    font-family: FractionFont;
  }
</style>
<math>
  <mrow style="border: 30px solid blue; padding: 20px;">
    <mfrac style="padding: 0; color: gray">
      <mspace width="120px" height="60px" depth="60px"></mspace>
      <mspace width="120px" height="60px" depth="60px"></mspace>
    </mfrac>
  </mrow>
</math>
